% latex table generated in R 4.4.1 by xtable 1.8-4 package
% Mon Aug 25 16:10:32 2025
\begin{table}[ht]
\centering
\begin{tabular}{lccccc}
  \hline
 & 1 & 2 & 3 & 4 & p\_value \\ 
   & All & Ever-treated & Never-treated & N. difference (2 vs. 3) & p-value \\ 
   \hline
ammonia &     0.138 &     0.133 &     0.138 & -0.010 & 0.104 \\ 
    & (0.341) & (0.340) & (0.341) &  &  \\ 
  phosphorous &     0.150 &     0.155 &     0.149 &  0.017 & 0.021 \\ 
    & (0.258) & (0.222) & (0.262) &  &  \\ 
  total kjedahl nitrogen &     0.630 &     0.538 &     0.643 & -0.120 & 0.000 \\ 
    & (0.687) & (0.505) & (0.708) &  &  \\ 
  restored wetlands (acres) &    26.544 &   247.212 &     0.000 &  0.321 & 0.000 \\ 
    & (263.433) & (769.285) & (0.000) &  &  \\ 
  restored wetlands (prop) &     0.001 &     0.010 &     0.000 &  0.310 & 0.000 \\ 
    & (0.011) & (0.031) & (0.000) &  &  \\ 
  restored wetland (0/1) &     0.046 &     0.425 &     0.000 &  0.859 & 0.000 \\ 
    & (0.209) & (0.494) & (0.000) &  &  \\ 
  ppt &    85.100 &    87.095 &    84.860 &  0.026 & 0.000 \\ 
    & (62.137) & (61.298) & (62.233) &  &  \\ 
  temp &    13.606 &    13.108 &    13.666 & -0.040 & 0.000 \\ 
    & (9.633) & (9.961) & (9.591) &  &  \\ 
  HUC12 acres & 25823.514 & 29200.166 & 25417.347 &  0.159 & 0.000 \\ 
    & (19005.896) & (13732.261) & (19505.291) &  &  \\ 
  agland &     0.406 &     0.589 &     0.384 &  0.574 & 0.000 \\ 
    & (0.294) & (0.196) & (0.297) &  &  \\ 
  developed &     0.100 &     0.073 &     0.103 & -0.147 & 0.000 \\ 
    & (0.174) & (0.101) & (0.181) &  &  \\ 
  grass/shrub &     0.126 &     0.043 &     0.136 & -0.349 & 0.000 \\ 
    & (0.234) & (0.109) & (0.243) &  &  \\ 
  treecover &     0.262 &     0.147 &     0.276 & -0.412 & 0.000 \\ 
    & (0.269) & (0.143) & (0.277) &  &  \\ 
  water &     0.038 &     0.039 &     0.038 &  0.013 & 0.002 \\ 
    & (0.085) & (0.053) & (0.089) &  &  \\ 
  TRI ammonia &   291.675 &   319.816 &   288.290 &  0.002 & 0.641 \\ 
    & (18232.169) & (6464.508) & (19166.909) &  &  \\ 
  TRI phosphorus &     0.108 &     0.000 &     0.121 & -0.008 & 0.003 \\ 
    & (15.033) & (0.000) & (15.911) &  &  \\ 
  animal units &  2293.404 &  3123.888 &  2181.229 &  0.223 & 0.000 \\ 
    & (2553.378) & (3488.638) & (2377.148) &  &  \\ 
   \hline
Observations & 175624 & 18857 & 156767 &   &  \\ 
  N HUC12 & 9102 & 348 & 8754 &   &  \\ 
   \hline
\end{tabular}
\end{table}
